US4268350A - Method of treating pulp bleaching effluents - Google Patents
Method of treating pulp bleaching effluents Download PDFInfo
- Publication number
- US4268350A US4268350A US06/076,745 US7674579A US4268350A US 4268350 A US4268350 A US 4268350A US 7674579 A US7674579 A US 7674579A US 4268350 A US4268350 A US 4268350A
- Authority
- US
- United States
- Prior art keywords
- alkali
- ultrafiltration
- stage
- concentrate
- permeate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000004076 pulp bleaching Methods 0.000 title claims 2
- 238000000108 ultra-filtration Methods 0.000 claims abstract description 27
- 239000003513 alkali Substances 0.000 claims abstract description 22
- 238000004061 bleaching Methods 0.000 claims abstract description 19
- 239000012466 permeate Substances 0.000 claims abstract description 14
- 238000004140 cleaning Methods 0.000 claims abstract description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 29
- 239000012141 concentrate Substances 0.000 claims description 16
- 235000011121 sodium hydroxide Nutrition 0.000 claims description 10
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 7
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 5
- 150000001805 chlorine compounds Chemical class 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 150000002989 phenols Chemical class 0.000 claims description 2
- 238000007599 discharging Methods 0.000 claims 1
- 150000004045 organic chlorine compounds Chemical class 0.000 claims 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 abstract description 12
- 239000011780 sodium chloride Substances 0.000 abstract description 6
- 238000000605 extraction Methods 0.000 abstract description 5
- KZBUYRJDOAKODT-UHFFFAOYSA-N Chlorine Chemical class ClCl KZBUYRJDOAKODT-UHFFFAOYSA-N 0.000 abstract 1
- 239000000460 chlorine Substances 0.000 description 27
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 23
- 229910052801 chlorine Inorganic materials 0.000 description 23
- 241000196324 Embryophyta Species 0.000 description 15
- 239000000126 substance Substances 0.000 description 7
- 229920005610 lignin Polymers 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 5
- 239000000706 filtrate Substances 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- 238000004064 recycling Methods 0.000 description 5
- 229910021653 sulphate ion Inorganic materials 0.000 description 5
- OSVXSBDYLRYLIG-UHFFFAOYSA-N dioxidochlorine(.) Chemical compound O=Cl=O OSVXSBDYLRYLIG-UHFFFAOYSA-N 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 239000004155 Chlorine dioxide Substances 0.000 description 2
- 229920002678 cellulose Polymers 0.000 description 2
- 239000001913 cellulose Substances 0.000 description 2
- 235000019398 chlorine dioxide Nutrition 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- WQYVRQLZKVEZGA-UHFFFAOYSA-N hypochlorite Chemical compound Cl[O-] WQYVRQLZKVEZGA-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000001556 precipitation Methods 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical class [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 150000001720 carbohydrates Chemical class 0.000 description 1
- 235000014633 carbohydrates Nutrition 0.000 description 1
- 238000005660 chlorination reaction Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 239000004035 construction material Substances 0.000 description 1
- 239000000356 contaminant Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000003546 flue gas Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 229910001504 inorganic chloride Inorganic materials 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 159000000014 iron salts Chemical class 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000011045 prefiltration Methods 0.000 description 1
- 238000004537 pulping Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000012216 screening Methods 0.000 description 1
- 238000005201 scrubbing Methods 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D61/00—Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
- B01D61/14—Ultrafiltration; Microfiltration
- B01D61/145—Ultrafiltration
- B01D61/146—Ultrafiltration comprising multiple ultrafiltration steps
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/44—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis
- C02F1/444—Treatment of water, waste water, or sewage by dialysis, osmosis or reverse osmosis by ultrafiltration or microfiltration
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/0021—Introduction of various effluents, e.g. waste waters, into the pulping, recovery and regeneration cycle (closed-cycle)
- D21C11/0028—Effluents derived from the washing or bleaching plants
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S162/00—Paper making and fiber liberation
- Y10S162/08—Chlorine-containing liquid regeneration
Definitions
- Oxygen bleaching is an established technique for sulphate pulp processing and certain branches of sulphite pulp processing, and has been responsible for reducing the discharge of bleaching plant contaminants by about one half.
- the out-flow from existing bleaching plants can also be treated externally in treatment units connected at the end of the bleaching plant.
- Add-on systems to existing plants primarily involve precipitation, adsorption, biological treatment or ultrafiltration.
- Adsorption cleaning is especially suitable where large volumes of water containing small amounts of impurities are concerned.
- the impurities fasten onto an adsorbent medium, such as activated carbon or an ion exchange material, which is regenerated after saturation; an operation which is, with today's technology, both expensive and laborious.
- Biological cleaning is a technique which is also expensive, because the necessary lagoons often involve large investments.
- Aerated lagoons in combination with ultrafiltration are otherwise an ideal solution, primarily because those substances which are most easily degraded can only be removed to a small degree by ultrafiltration. The easily degradable substances are thus removed more quickly in the subsequent lagoon with a more or less complete cleaning as a result.
- An advantage of this method is that it does not require any chemical additives.
- the normal sequence in a bleaching plant includes the steps chlorine, alkali, hypochlorite, chlorine dioxide, alkali, chlorine dioxide, i.e. in the usual notation CEHDED.
- the major portion of the discharge from the bleaching plant comes from the first alkali stage, E 1 , and this amount is also the easiest to handle with regard to volume.
- Ultrafiltration of the discharge from the E 1 stage has been shown to function well in practice and provide improvement in cleaning at reasonable costs. Ultrafiltration is easily connectable to the E 1 stage of the bleaching plant and has obvious advantages over other methods.
- An ultrafiltration unit consists of a prefilter for removing fibers and other suspended material in addition to the main ultrafiltration unit, which consists of a number of cells or stages coupled in series, in which the E filtrate is successively reduced in volume by removal of the permeate.
- the ultrafiltration is carried out at an input pressure of, for example, 5-10 bar and the pressure drop in each cell is overcome with a pressure booster pump. By varying the operating pressure and the temperature, variations in load can be met.
- the boundary for separation lies at a molecular weight of 1000-2000 and the concentrate contains high molecular lignin remnants and carbohydrates while the permeate contains the majority of the salts and low molecular organic substance from the E stage.
- the present invention relates to a method of substantially reducing the chloride increase which is produced by the fraction of organically bonded chlorine after the incineration of the concentrate in the soda boiler.
- the major portion of the splitting takes place during the first hours of the treatment.
- such a splitting is used to reduce the percentage of organic chlorine in the concentrate to the soda recovery boiler, by inserting a treatment stage with alkali in the ultrafiltration. After a first ultra-filtration stage the concentrate produced is treated with caustic soda and is then treated further in a second ultra-filtration stage.
- the sodium chloride formed by splitting with alkali is present in the permeate and produces upon recycling to the recovery system an appreciably reduced chloride increase.
- the strongly alkaline, second permeate which also contains a relatively large amount of organic substance returns to the alkali stage as its alkali source.
- the caustic soda is returned in this manner to the process stage which it is normally intended for and there are no losses.
- a portion of the alkali is added directly to the extraction stage 1 without first having been used for the chlorine lignin hydrolysis.
- the filtrate from the first alkali stage in a bleaching plant for sulphate pulp was introduced into the 12-cell ultrafiltration unit in an amount of 10 m 3 /t pulp and containing 8 kg inorganically bonded chlorine/t pulp and 4 kg/t organically bonded chlorine. After passage through 10 cells, 9.6 m 3 /t permeate was taken out containing 7.7 kg/t of inorganic chlorine and 0.4 kg/t of organic chlorine. This permeate I could be released directly as effluent to a recipient without causing any ecological disturbances.
- the concentrate was treated with 0.1 m 3 /t caustic soda with a concentration of 250 g/l at a temperature of 100° C.
- 0.4 m 3 /t permeate II was obtained therefrom containing 2.0 kg/t inorganic chlorine and 0.1 kg/t organic chlorine and 17 kg/t NaOH, as well as 0.1 m 3 /t concentrate with 0.5 kg/t inorganic chlorine, 1.3 kg/t organic chlorine and 5 kg/t NaOH.
- the permeate II was conducted to the alkali stage E 1 as a portion of the volume of alkali required there, and the concentrate went to the soda furnace for burning and use of the alkali in recycling.
Landscapes
- Engineering & Computer Science (AREA)
- Water Supply & Treatment (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Wood Science & Technology (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Paper (AREA)
- Detergent Compositions (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7811089A SE414411B (sv) | 1978-10-25 | 1978-10-25 | Sett att rena utslepp fran blekerier med ultrafiltrering |
| SE7811089 | 1978-10-25 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4268350A true US4268350A (en) | 1981-05-19 |
Family
ID=20336188
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/076,745 Expired - Lifetime US4268350A (en) | 1978-10-25 | 1979-09-18 | Method of treating pulp bleaching effluents |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4268350A (fi) |
| JP (1) | JPS604758B2 (fi) |
| CA (1) | CA1130023A (fi) |
| FI (1) | FI65830C (fi) |
| NO (1) | NO150955C (fi) |
| SE (1) | SE414411B (fi) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT377546B (de) * | 1983-02-25 | 1985-03-25 | Dieter J Becker | Verfahren zur reinigung von bei der zellstoffherstellung, insbesondere bei der chlorbleiche von zellstoff, anfallenden abwaessern |
| EP0454642A1 (en) * | 1990-04-23 | 1991-10-30 | Eka Nobel Ab | Reduction of halogenated organic compounds in spent bleach liquor |
| US5127992A (en) * | 1988-08-23 | 1992-07-07 | Sappi Limited | Elimination of bleach effluents |
| US5164043A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5164044A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5188708A (en) * | 1989-02-15 | 1993-02-23 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification followed by ozone relignification |
| US5211811A (en) * | 1989-02-15 | 1993-05-18 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification |
| US5310458A (en) * | 1989-06-06 | 1994-05-10 | Eka Nobel Ab | Process for bleaching lignocellulose-containing pulps |
| US5409570A (en) * | 1989-02-15 | 1995-04-25 | Union Camp Patent Holding, Inc. | Process for ozone bleaching of oxygen delignified pulp while conveying the pulp through a reaction zone |
| US5441603A (en) * | 1990-05-17 | 1995-08-15 | Union Camp Patent Holding, Inc. | Method for chelation of pulp prior to ozone delignification |
| US5554259A (en) * | 1993-10-01 | 1996-09-10 | Union Camp Patent Holdings, Inc. | Reduction of salt scale precipitation by control of process stream Ph and salt concentration |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4155845A (en) * | 1976-05-12 | 1979-05-22 | Rhone-Poulenc Industries | Treatment of pulp mill effluents |
-
1978
- 1978-10-25 SE SE7811089A patent/SE414411B/sv not_active IP Right Cessation
-
1979
- 1979-09-18 US US06/076,745 patent/US4268350A/en not_active Expired - Lifetime
- 1979-09-26 CA CA336,447A patent/CA1130023A/en not_active Expired
- 1979-10-02 JP JP54127242A patent/JPS604758B2/ja not_active Expired
- 1979-10-19 FI FI793244A patent/FI65830C/fi not_active IP Right Cessation
- 1979-10-24 NO NO793415A patent/NO150955C/no unknown
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4155845A (en) * | 1976-05-12 | 1979-05-22 | Rhone-Poulenc Industries | Treatment of pulp mill effluents |
Non-Patent Citations (2)
| Title |
|---|
| Empire State Paper Research Institute, Research Report No. 69, 10/1/78. * |
| Revue ATIP, vol. 28, No. 1, 1974, p. 9-15. * |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT377546B (de) * | 1983-02-25 | 1985-03-25 | Dieter J Becker | Verfahren zur reinigung von bei der zellstoffherstellung, insbesondere bei der chlorbleiche von zellstoff, anfallenden abwaessern |
| US5127992A (en) * | 1988-08-23 | 1992-07-07 | Sappi Limited | Elimination of bleach effluents |
| US5188708A (en) * | 1989-02-15 | 1993-02-23 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification followed by ozone relignification |
| US5409570A (en) * | 1989-02-15 | 1995-04-25 | Union Camp Patent Holding, Inc. | Process for ozone bleaching of oxygen delignified pulp while conveying the pulp through a reaction zone |
| US5211811A (en) * | 1989-02-15 | 1993-05-18 | Union Camp Patent Holding, Inc. | Process for high consistency oxygen delignification of alkaline treated pulp followed by ozone delignification |
| US5310458A (en) * | 1989-06-06 | 1994-05-10 | Eka Nobel Ab | Process for bleaching lignocellulose-containing pulps |
| US5149442A (en) * | 1990-04-23 | 1992-09-22 | Eka Nobel Ab | Reduction of halogenated organic compounds in spent bleach liquor |
| EP0454642A1 (en) * | 1990-04-23 | 1991-10-30 | Eka Nobel Ab | Reduction of halogenated organic compounds in spent bleach liquor |
| US5164044A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5164043A (en) * | 1990-05-17 | 1992-11-17 | Union Camp Patent Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with ozone |
| US5296099A (en) * | 1990-05-17 | 1994-03-22 | Union Camp Holding, Inc. | Environmentally improved process for bleaching lignocellulosic materials with oxygen, ozone and chlorine dioxide |
| US5441603A (en) * | 1990-05-17 | 1995-08-15 | Union Camp Patent Holding, Inc. | Method for chelation of pulp prior to ozone delignification |
| US5554259A (en) * | 1993-10-01 | 1996-09-10 | Union Camp Patent Holdings, Inc. | Reduction of salt scale precipitation by control of process stream Ph and salt concentration |
| US5693184A (en) * | 1993-10-01 | 1997-12-02 | Union Camp Patent Holding, Inc. | Reduction of salt scale precipitation by control of process stream pH and salt concentration |
Also Published As
| Publication number | Publication date |
|---|---|
| CA1130023A (en) | 1982-08-17 |
| FI793244A (fi) | 1980-04-26 |
| NO150955B (no) | 1984-10-08 |
| JPS604758B2 (ja) | 1985-02-06 |
| FI65830B (fi) | 1984-03-30 |
| NO150955C (no) | 1985-01-16 |
| NO793415L (no) | 1980-04-28 |
| SE414411B (sv) | 1980-07-28 |
| JPS5559882A (en) | 1980-05-06 |
| FI65830C (fi) | 1984-07-10 |
| SE7811089L (fi) | 1980-04-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| STCF | Information on status: patent grant |
Free format text: PATENTED CASE |